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Discussion Starter · #1 ·
Hello fellow performance car enthusiasts!

I am new to these engines, and I would like a description, and pictures of, the valvetrain of their respective head, and hardware.

Specifically, I am interested in the capability of the valvetrain, I keep reading words like "additional lift" which makes me think of honda's additional rocker arm, and yet I find */% camshaft retard/advance within the power FC management software- making me think that it is in fact an electronically controlled camshaft degree-

for the intake cam? the exhaust cam? BOTH? Does it change lift ALSO? What does it look like? An FSM would be great also- thanks!
 

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Sometimes it's hard to get a feel for the actual device, when only reading papers..

In a nut shell.. the 1ZZ is the base model.. it's an econo Box motor.. and built for gas millage..

It has a Fixed Exhaust Cam Timing, and a Variable Intake Cam Timing through a range of about 30Deg if I remember my Numbers properly. Its done with a Oil Actuator moving the Timing of the Intake Cam, and a feed back loop checking Cam Sig Phasing to Crank Sig Phasing.. so a Smart Device is needed to keep the Cam Timing, if it's not full retard or Full advance.. That is where the i comes from in VVTi ( Intelligent )

The 2ZZ was built to kick ass on the 1ZZ.. it was built as a performance motor.. it took all the success that they had on the development of the 1ZZ VVTi ( Variable Valve Timing with Intelligent Feed Back ) and added a 'Lift' Feature.. this is a Slipper foot that will drop under a cam lobe to increase Valve Lift and also increase Duration, of the Valve Timing, for use at higher RPM ranges.. to increase breathing of the engine..

The Lift is done to the Intake and Exhaust Valve train, and the VVTi is still only done on the Intake cam..

Other changes were done to the Head to increase breathing.. like Valve Stem Angle to Port..

Cap
 

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Discussion Starter · #4 · (Edited)
thank you very much! I read through the documentation and have prepared more questions!
I also found this which was helpful:http://2zzge.com/library/1ZZFE/1zzfe.pdf
Notes:

1. intake camshaft timing
The intake cam advance is under control of the ECU, for ALL engine speeds!
"The system changes valve timing over the entire speed range in accordance to engine speed and load."


2. valve LIFT
It seems as though this feature is intended to be "locked"- we cannot adjust the moment of the valve lift increase (via ECU).
"...also changes valve lift and event angles at 6000rpm from low to high"


3. valve springs
A typical problem with any combustion engine relying on valvesprings is that a valvetrain instability may occur at specific frequencies which affects the valve closing event, it has been given names such as "valve float".
I have noted that this documentation includes research directed towards the "stability" of the valvetrain, specifically with regards to the valve springs and the closing events.

"Valve lift acceleration was changed to improve
resonance, and rocker arm rigidity was increased to
improve deflection."


Many aftermarket camshafts alter the lift characteristics, which would affect the resonant frequencies, since the fix was applied to the camshaft instead of the springs themselves. Changing valvesprings would seem to be a fix, except that this typically means a stronger spring, which may not be a reliable change, since rocker arm durability/deflection was tested and confirmed for OEM camshafts ONLY.... there is no way to guarantee abnormal wear and tear associated with aftermarket valve springs will not occur.

My question here is (#3)... How is the community, over the past years, handling and testing the aftermarket valve springs? Have there been component failures due to the aftermarket springs? Have there been issues with breaking components or unreliable valve seals? has anybody driven one of these engines for 150,000 miles with aftermarket camshafts/springs?
Does anybody have OEM flow numbers for the head at variable lifts?

4. Compression, turbochargers, cast components.

I see the engine is designed around the idea of lightweight naturally aspirated fuel economy fun.
As for turbocharging, the compression seems a bit high to maximize the potential of pump gas. I feel that with 9:1 compression the engine should be able to produce about 400 horsepower by 7,000rpm with 93 octane, if it is anything like a typical 4-cylinder engine.

But because the compression is higher than 9:1, I would expect a limitation to be imposed by the octane being used. For 93 octane, without an intercooler, 10:1 compression would be safe up to about 7psi of efficient pressure above atmospheric, depending of course upon the design and shape of the combustion chambers, as well as any helmholtz acoustic tuning that was done which might improve VE at specific points, giving an abnormally high peak torque number which may instigate pre-ignition... That is why #4 is here... I must ask:

A. What are the typical power and boost numbers acheived while using the 1zz AND 2zz engines with OEM components/compression and a turbocharger?
B. What is the capability of the water/air intercooler I see being used? Can it support 30lb/min? 40lb/min?
C. Durability... are there MANY cast piston failures when turbocharging the OEM bottom end? If so, where associated, the piston ring likely?

Guesses, just for fun:

I would guess, that maximum safe boost is about 10psi on the 1zz while using an air/water intercooler. And 7psi for the 2zz with the same intercooler.
While using the OEM bottom end. Assumed compressor flow of 32-35 lb/min maximum for best efficiency island characteristics.
 

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Don't get me wrong, this would be an interesting discussion ten years ago and there has been many discussions and real world performance with various parts as well as it's pitfalls.

All of this can be found using the search engine on this site. Everything you need to know about valve springs, cams and low compression pistons with dyno graphs from owner discussions. If you are interested I highly recommend doing a bit of research.
 

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Discussion Starter · #6 ·
Don't get me wrong, this would be an interesting discussion ten years ago and there has been many discussions and real world performance with various parts as well as it's pitfalls.

All of this can be found using the search engine on this site. Everything you need to know about valve springs, cams and low compression pistons with dyno graphs from owner discussions. If you are interested I highly recommend doing a bit of research.
Ah, but thats just it. digging through ten years of posts, reading thousands of paragraphs....
I am interested, yes, but from the standpoint of safety and tuning ONLY. I do not OWN one of these engines, I intend only to TUNE one of these engines.
Without knowing the answers to the question I pose, I can still do just that. Only it will be more of an adventure!

I get the answers I need I might create write-up with pictures about tuning a turbocharged 1zz engine complete with PFC maps and dyno graphs. That will give back to the community.
 

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Ah, but thats just it. digging through ten years of posts, reading thousands of paragraphs....
I am interested, yes, but from the standpoint of safety and tuning ONLY. I do not OWN one of these engines, I intend only to TUNE one of these engines.
Searching is what I do as well as everyone at this site does to get good information. There is a wealth of information at your fingertips from those that have tuned this engine that are no longer with us. Trust me when I say that your best information comes from the search not from a request.
Another place to get more information is on Newcelica.org as they have much to offer on their stickies. After researching this information you will be prepared to ask relevant questions rather then have someone spoon feed you.
 

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Discussion Starter · #8 ·
Searching is what I do as well as everyone at this site does to get good information. There is a wealth of information at your fingertips from those that have tuned this engine that are no longer with us. Trust me when I say that your best information comes from the search not from a request.
Another place to get more information is on Newcelica.org as they have much to offer on their stickies. After researching this information you will be prepared to ask relevant questions rather then have someone spoon feed you.
Ok, after my quantitative analysis exam, inorganic chemistry exam, calculus 3 exam, genetics exam, and biochemistry exams.... Yarrr I will find the time somehow.
I am all for searching. It just takes... time
Will you at least tell me how close my guesses are?
 

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I get the answers I need I might create write-up with pictures about tuning a turbocharged 1zz engine complete with PFC maps and dyno graphs. That will give back to the community.
We have all of that and more from members over the years. We also have free software developed by one of our members and a lot of support for those that need it.
I'ts great if you want to do it but if you have to ask questions like these it tells me that your experience is sub par.

So I will ask you what can you do that is different and better then what we already have?

To find the answer to this question one must search.
 

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Ok, after my quantitative analysis exam, inorganic chemistry exam, calculus 3 exam, genetics exam, and biochemistry exams.... Yarrr I will find the time somehow.
I am all for searching. It just takes... time
Will you at least tell me how close my guesses are?
I would but I am also quiet busy at the moment like you as I have to find my sunblock for my vacation.

I would like to tell you how close your guess are but I will do one better, I will teach you how to fish.
Search :noobbananadance: :lol:
 

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Ok, after my quantitative analysis exam, inorganic chemistry exam, calculus 3 exam, genetics exam, and biochemistry exams.... Yarrr I will find the time somehow.
I am all for searching. It just takes... time
Your time is no more or less valuable than that of anyone else.

This,



Is not an option.
 

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Discussion Starter · #12 · (Edited)
Already said I would do it. Why are you still posting? Why am I still posting? /troll
as to sub par experience... Well, lets see. My first time ever hearing about a 1zz engine was.... three days ago! So yes, I would say, sub par best describes my experience level with this particular engine...

On the other hand, all internal combustion engines operate on similar principles. My questions are regarding frailty- something very specific, per engine.

So this topic will now encase what I "discover". Nobody needs to post here except me... ever again, unless YOU have a question! No more questions will be asked by ME. Only answers from here on out.

g'day.
 

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Discussion Starter · #14 · (Edited)
I want to learn everything I can about this engine. I was willing to risk posting on a forum where I thought responsible professionals would give me the advice that the forum pretends to represent. Usually you come to a place and you are there to GET HELP. But when I come to this place for HELP, I get baby photos. This is what the forum represents? People asking for help getting baby photos instead?
 

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[QUOTE=kingt
 

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I want to learn everything I can about this engine. I was willing to risk posting on a forum where I thought responsible professionals would give me the advice that the forum pretends to represent. Usually you come to a place and you are there to GET HELP. But when I come to this place for HELP, I get baby photos. This is what the forum represents? People asking for help getting baby photos instead?
Professional: n. Someone who gets paid for their expert advice and assistance.

As a college student, in the midst of finals, you should already be familiar with the phrase: "Do your own banmepleaseing homework Bubba."
 

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I get baby photos. This is what the forum represents? People asking for help getting baby photos instead?
You also got a picture of a mother and one of your pram after you had thrown all your toys out in petulance.:lol:

But, just for you, here is another.

 
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